Blood Composition
Blood is a tissue composed of a cellular part and a non-cellular liquid part. Blood has a number of functions including transporting various materials around the body. Blood also helps to keep the internal environment constant, by distributing heat throughout the body from the actively respiring tissues (liver & muscles) as well as transporting materials that need to be removed from the body (carbon dioxide & urea).
Most materials are carried by the blood plasma. Only oxygen not carried by the plasma.
| SUBSTANCE | CARRIED FROM | CARRIED BY | CARRIED TO |
|---|---|---|---|
| Oxygen | Lungs | Red Blood Cells | Whole of the body |
| Carbon Dioxide | Whole of the body | Plasma | Lungs |
| Food (e.g. glucose, amino acids, fats etc) | Small intestine | Plasma | Whole of the body |
| Urea | Liver | Plasma | Kidneys |
| Hormones (e.g. insulin) | Glands | Plasma | Target organs |
